Add a new iommufd_viommu core structure to represent a vIOMMU instance in the user space, typically backed by a HW-accelerated feature of an IOMMU, e.g. NVIDIA CMDQ-Virtualization (an ARM SMMUv3 extension) and AMD Hardware Accelerated Virtualized IOMMU (vIOMMU). Define a new iommufd_viommu_ops to hold the free op and any future op. A driver should embed this core structure in its driver viommu structure and call the new iommufd_viommu_alloc() helper to allocate a core/driver structure bundle and fill its core viommu->ops: struct my_driver_viommu { struct iommufd_viommu core; .... }; static const struct iommufd_viommu_ops my_driver_viommu_ops = { .free = my_driver_viommu_free, }; struct my_driver_viommu *my_viommu = iommufd_viommu_alloc(my_driver_viommu, core); my_viommu->core.ops = &my_driver_viommu_ops; Lastly, add viommu_alloc to iommu_ops so iommufd can link to the driver to allocate a viommu object. Any future viommu op will be added to the new struct iommufd_viommu_ops. Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> --- drivers/iommu/iommufd/viommu.c | 2 ++ include/linux/iommu.h | 15 ++++++++++++++ include/linux/iommufd.h | 38 ++++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+) diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c index f77d6972d552..3886b1dd1f13 100644 --- a/drivers/iommu/iommufd/viommu.c +++ b/drivers/iommu/iommufd/viommu.c @@ -17,3 +17,5 @@ return NULL; \ return container_of(obj, struct iommufd_##name, obj); \ } + +viommu_struct_alloc(viommu); diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 2e925b5eba53..4d4461146288 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -145,6 +145,8 @@ struct iopf_queue { struct mutex lock; }; +struct iommufd_viommu; + /* iommu fault flags */ #define IOMMU_FAULT_READ 0x0 #define IOMMU_FAULT_WRITE 0x1 @@ -527,6 +529,14 @@ static inline int __iommu_copy_struct_from_user_array( * @of_xlate: add OF master IDs to iommu grouping * @is_attach_deferred: Check if domain attach should be deferred from iommu * driver init to device driver init (default no) + * @viommu_alloc: Allocate an iommufd_viommu as a user space IOMMU instance, + * associated to a nested parent @domain, for iommu-specific + * hardware acceleration. The @viommu_type must be defined in + * the include/uapi/linux/iommufd.h header. + * It is suggested to call iommufd_viommu_alloc() helper for + * a bundled allocation of the core and the driver structure, + * and a driver in gernal should assign an iommufd_viommu_ops + * to the core structure's viommu->ops. * @dev_enable/disable_feat: per device entries to enable/disable * iommu specific features. * @page_response: handle page request response @@ -570,6 +580,11 @@ struct iommu_ops { int (*of_xlate)(struct device *dev, const struct of_phandle_args *args); bool (*is_attach_deferred)(struct device *dev); + /* User space instance allocation by the iommu driver */ + struct iommufd_viommu *(*viommu_alloc)(struct device *dev, + unsigned int viommu_type, + struct iommu_domain *domain); + /* Per device IOMMU features */ int (*dev_enable_feat)(struct device *dev, enum iommu_dev_features f); int (*dev_disable_feat)(struct device *dev, enum iommu_dev_features f); diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index a0cb08a4b653..650acfac307a 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -16,6 +16,7 @@ struct iommufd_device; struct page; struct iommufd_ctx; struct iommufd_access; +struct iommufd_hwpt_paging; struct file; struct iommu_group; @@ -77,6 +78,26 @@ void iommufd_access_detach(struct iommufd_access *access); void iommufd_ctx_get(struct iommufd_ctx *ictx); +struct iommufd_viommu { + struct iommufd_object obj; + struct iommufd_ctx *ictx; + struct iommu_device *iommu_dev; + struct iommufd_hwpt_paging *hwpt; + + const struct iommufd_viommu_ops *ops; + + unsigned int type; +}; + +/** + * struct iommufd_viommu_ops - viommu specific operations + * @free: Free all driver-specific parts of an iommufd_viommu. The memory + * of the entire viommu will be free-ed by iommufd core + */ +struct iommufd_viommu_ops { + void (*free)(struct iommufd_viommu *viommu); +}; + #if IS_ENABLED(CONFIG_IOMMUFD) struct iommufd_ctx *iommufd_ctx_from_file(struct file *file); struct iommufd_ctx *iommufd_ctx_from_fd(int fd); @@ -93,6 +114,8 @@ int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, int iommufd_vfio_compat_ioas_get_id(struct iommufd_ctx *ictx, u32 *out_ioas_id); int iommufd_vfio_compat_ioas_create(struct iommufd_ctx *ictx); int iommufd_vfio_compat_set_no_iommu(struct iommufd_ctx *ictx); + +struct iommufd_viommu *_iommufd_viommu_alloc(size_t size); #else /* !CONFIG_IOMMUFD */ static inline struct iommufd_ctx *iommufd_ctx_from_file(struct file *file) { @@ -133,5 +156,20 @@ static inline int iommufd_vfio_compat_set_no_iommu(struct iommufd_ctx *ictx) { return -EOPNOTSUPP; } + +static inline struct iommufd_viommu *_iommufd_viommu_alloc(size_t size) +{ + return NULL; +} #endif /* CONFIG_IOMMUFD */ + +/* + * Helpers for IOMMU driver to allocate driver structures that will be freed by + * the iommufd core. A driver is only responsible for its own struct cleanup. + */ +#define iommufd_viommu_alloc(drv_struct, member) \ + container_of(_iommufd_viommu_alloc(sizeof(struct drv_struct) + \ + BUILD_BUG_ON_ZERO(offsetof( \ + struct drv_struct, member))), \ + struct drv_struct, member) #endif -- 2.43.0